save facets following the order of the admin form.

lib/Alchemy/Phrasea/Controller/Admin/SearchEngineController.php

@@ -33,7 +33,19 @@ class SearchEngineController extends Controller
         $form->handleRequest($request);
 
         if ($form->isValid()) {
-            $this->saveElasticSearchOptions($form->getData());
+            /** @var ElasticsearchOptions $data */
+            $data = $form->getData();
+            // $q = $request->request->get('elasticsearch_settings');
+            $facetNames = [];   // rebuild the data "_customValues/facets" list following the form order
+            foreach($request->request->get('elasticsearch_settings') as $name=>$value) {
+                $matches = null;
+                if(preg_match('/^facets:(.+):limit$/', $name, $matches) === 1) {
+                    $facetNames[] = $matches[1];
+                }
+            }
+            $data->reorderAggregableFields($facetNames);
+
+            $this->saveElasticSearchOptions($data);
 
             return $this->app->redirectPath('admin_searchengine_form');
         }

lib/Alchemy/Phrasea/SearchEngine/Elastic/ElasticsearchOptions.php

@@ -257,6 +257,18 @@ class ElasticsearchOptions
         return $this->_customValues['facets'];
     }
 
+    // set to change the facets order during admin/form save
+    public function reorderAggregableFields($facetNames)
+    {
+        $newFacets = [];
+        foreach ($facetNames as $name) {
+            if(($facet = $this->getAggregableField($name)) !== null) {
+                $newFacets[$name] = $facet;
+            }
+        }
+        $this->_customValues['facets'] = $newFacets;
+    }
+
     public function getActiveTab()
     {
         return $this->activeTab;